Patent GB-679720-A (GB)
Title: Improvements in or relating to cinematograph projectors or apparatus for producing or reproducing strip sound records
IPC: G11B25/10
Filed: 1949-05-27
Abstract: 679,720. Kinematograph projectors. D'ORNELLAS, M. L. May 27, 1949 [July 7, 1948], No. 14231/49. Class 97 (i). [Also in Group XXXVIII] The projector has a multiple spool case having a number of compartments with feed and take-up spools in each, the spool case being movable bodily to bring a selected film into position for projection. In the form shown in Figs. 1 and 2, the motor 25 drives continuously, through belts, shafts 30, 45, 60, 65. The multiple spool case 70 is made up from spaced plates 75<SP>1</SP>, 75, 75a, 75b, 75c hinged together and secured by a latch 78. These plates carry inwardly projecting bearings 82, 102 for feed and take-up spools 84, 100 and also support hollow sprockets 85 and associated rollers 87, 97 by which the film is fed to and from a loop for projection purposes. A film is selected for projection by moving the spool case bodily sideways by means of the handle 113 on a shaft 112 coupled to the case by a link 125. When the handle 113 is opposite one of the notches 126 one of the films is projected by light from the lamp 27 passing down a tube 35 and reflected by a prism 37. The shaft 30 carries a shutter 32. The rotation of the shaft 112, as the knob 113 is moved out of a notch 126, causes rotation of a shaft 120 through a rod 115 carried on arms 114 and engaging the slotted end of an arm 118. This latter rotation causes to move forwardly, away from the prisms 37, a box 40 which contains the projection lens and feed claw driven by flexible shaft 95 from the shaft 30. This movement frees the film for removal from the projecting position. The box 40 carries a switch engaging the edge of the film which is formed with a notch near the finish so that, when projection is complete, the switch is opened to stop projection and turn off the lamp until a fresh film is in the projecting position. As shown in Fig. 2, the left-hand film is in this position. The appropriate sprocket 85 is driven by spring fingers 109, on a member 107 at the end of the shaft 65, engaging an internal spline. The take-up spool 100 is driven by spring fingers 108, on a member 105 at the end of the shaft 60, engaging projections in the spool core. Any film previously shown is rewound after removal from the projecting position. For this purpose the shaft 52, on which the hollow shaft 45 is supported, carries stationary electromagnets 135a &c. A spring member 136 opposite each magnet, has a portion lying outside the shaft 45 in a longitudinal groove 137 therein, and arms projecting inwardly through holes in the tube. Normally these arms are slightly divergent, as shown opposite the magnets 135b, 135c. Energization of the magnet pulls the arms inwardly, as shown at the magnet 135a so that the portion lying in the grooves 137 is bowed outwardly to engage projections in the core of the spool 84. Contacts on the main case and spool case control the energization of the magnet 135a &c. to ensure that every film except that in the projecting position is rewound until rewinding is stopped by a notch near the film end. A switch is provided by which rewinding may be stopped if it is desired to project part of a film and subsequently return to it. In a modified embodiment provision is made also for sound reproduction. Fig. 10 shows a push-button device for selecting the film for projection. When one of the buttons 218 is depressed a circuit is completed through a contact 220 and a disc 215, on the shaft 188, to energize a magnet 213 and free a latch 211 from one of four racks on the inside of the frame 181 mounted in a guide frame 183. This frees the frame to be driven in a rectangular motion determined by the engagement of a fixed finger 195 in parallel slots 190, 191 connected by end slots 193, 194. The frame 181 is driven in this movement by a gear 187 also on the shaft 188 driven through bevel gearing from a spring 204 tensioned by the motor 25 through a friction device 206. This movement continues until the depressed contact 220 registers with one of a number of insulating areas 216a &c. on the disc 215. The latch 211 is then released. The frame 181 is coupled to the multiple spool case by a link 180. The various stopping positions so determined bring different films to the projecting position. Operation of any button pushes a rod 225 to turn a crank 227 coupled by a cable to a crank on a shaft 230 corresponding to 120 in Fig. 1.